Improvement in electric circuit-closers for fire-alarms



:r. o. FOWLER, Jr.

ELECTRIC CIRCUIT-CLOSER FOR FIRE-ALARMS. lib-182,997.

Patented Oct.10.1876.

jmwzfarr JAMES ROSGOOD 5;. CO BOSTON.

UNITED STATES? PATENT OFFICE.

JONATHAN 0. FOWLER, JR, or Bunsen, WISCONSIN.

IMPROVEMENT IN ELECTRIC CIRCUIT-CLQSERS FOR FIRE-ALARMS.

Specification forming part of Letters Patent No. 182,997, dated October10, 1876; application filed April 21, 1876.

To all whom it may concern:

Be it known that I, JONATHAN O. FOW- LER, Jr., of Hudson, in the countyof St. Groix and State of Wisconsin, have invented certain Improvementsin Fire-Alarms, of which the following is a specification:

The object of my invention is to produce an automatic electrical alarmwhich will act with certainty whenever the temperature of thesurrounding air reaches a fixed limit, and which shall at the same timebe cheap and simple in its construct-ion, and free from liability toderangement; and to this end the invention consists in the combinationof a self-acting circuit-closing device, with a hotair match so appliedthat its ignition causes the release of the device, so that it may closethe circuit.

I am aware that numerous automatic electrical alarms to be actuated byhot air have been hitherto inventedsuch, for example, as expansion-bars,compound flexion bars, and mercurial columns; but all such devices areexpensive, delicate in construction, and, owing to the delicacy ofadjustment required, unreliable in their action, and unfit for use byunskilled persons.

It is to overcome these difficulties, and produce a circuit-closingdevice which shall be cheap, durable, and reliable in its action, and

which can be properly attended by unskilled persons, that my inventionis intended; and these results I find I can attain by the application ofa hot-air match or fuse in such manner as to cause the positive releaseof a selfacting circuit-closer.

The form of the devices and their arrangement may be varied withoutchanging their principle of operation; but it is preferred to use one ofthe two arrangements represented in the accompanying drawings.

Figure 1 represents a side elevation of one form of my alarm, adjustedfor action; Fig. 2, the same, in action; Fig. 3, a view of the indicatoror alarm proper; Fig. 4, a view of a modified form of thecircuit-closing device.

A represents an electromagnetic alarm or indicator, located at anydesired point; B 0,

wires leading from the alarm to a battery, D, and'E a circuit-closingdevice, introduced into the circuit at the point which is to be guardedagainst fire.

In Figs. 1 and 2 the circuit-closer consists of a non-conducting plate,a, through which the ends of the severed wires are passed separately,and of a sliding rod, I), mounted in the plate a, and provided on oneend with a head or enlargement, and on the other with a spiral spring,which serves to draw the head up against the two ends of the wire, so asto complete the circuit and cause the action of the alarm.

The sliding rod is held back, so as to keep the circuit open, by meansof a cord, (1, as shown in Fig. 1.

Below the cord 01 there is mounted a hotair match, F, adapted to ignitewhen the air attains the temperature fixed upon as that at which thealarm is to be sounded.

When the match or fuse ignites it destroys the cord d, and therebyreleases the circuitcloser, which instantly completes the circuit, andcauses the action of the alarm.

The match or fuse is sustained in a metal plate, G, provided at its endswith two standards, one supporting the circuit-closing device and theother the end of the cord d, as shown.

In the device represented in Fig. 4 a hinged falling arm, 0, connectedwith one of the wires, has its free end sustained by a thin combustiblepin, g. A metal plate or bar, h, connected with the other wire, isarranged in such position that the arm, falling against it, willcomplete the circuit. The match or fuse is arranged below the pin 9, sothat when ignited it destroys the pin, and permits the arm 0 to fall.

It will be observed that although the device shown in Fig. 4 differsfrom that represented in Figs. 1 and 2, in closing by gravity instead ofby a spring, the match answers the same purpose in both cases.

It is obvious that in both instances the match or fuse can be applieddirectly, and without the interposition of the cord or strip tohold thecircuit'open; but it is considered match, arranged to release the deviceand better to have the match operate indirectly permit it to close thecircuit, as shown and to release the circuit-closer, as shown.described.

Having described my invention what I claim JONATHAN O. FOWLER, JR.

In an electrical fire-alarm, the combination Witnesses:

of a. self-acting circuit-closing device, held P. T. DODGE,

open, substantially as shown, and a hot-air WILL W. DODGE.

